PSLE A stationery kiosk is having a book sale.
The 1st book is at 5% discount.
The 2nd book is at 20% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Gillian and Sam each bought two books at the sale.
- Gillian's books were priced at $9 and $22. How much more did she pay for the 1st book than the 2nd book?
- Sam paid a total of $46.10 for his two books. He paid $10.90 more for the 1st book than for the 2nd book. What was the price of the 1st book before discount?
|
1st book |
2nd book |
Total amount |
Original price
|
100% $22 |
100% $9 |
|
Discount |
- 5% |
- 20% |
|
Sale price |
95% |
80% |
? |
(a)
Selling price of the 1st book
= 95% x 22
=
95100 x 22
= $20.90
Selling price of 2nd book
= 80% x 9
=
80100 x 9
= $7.20
Amount that Gillian paid more for the 1st book than the 2nd book
= 20.90 - 7.20
= $13.70
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 5% |
- 20% |
|
Sale price |
95%
|
80%
|
|
Compare 1st book and 2nd book |
1 u + $10.90 |
1 u |
$46.10 |
(b)
Sale price of the 1st book = 1 u + 10.90
Sale price of the 2nd book = 1 u
Total amount that Sam paid
= 1 u + 10.90 + 1 u
= 2 u + 10.90
2 u + 10.90 = 46.10
2 u = 46.10 - 10.90
2 u = 35.20
1 u = 35.20 ÷ 2 = 17.60
Sale price of the 1st book
= 1 u + 10.90
= $28.50
95% of the price = $28.50
100% of the price =
28.5095 x 100 = $30
Selling price of the 1st book before discount = $30
Answer(s): (a) $13.70; (b) $30